Cap-Free Neck End For A Filler Neck

ABSTRACT

A cap-free closeable neck end for a filler neck of a tank of a motor vehicle, the cap-free closeable neck including an upper entry space forming an insertion region for a fuel nozzle and being surrounded by a side wall, a lower sealing flap arranged in the upper entry space and a closing mechanism arranged above the lower sealing flap. The closing mechanism includes an upper filling opening and an upper cover, which in a closed state at least partially covers the upper filling opening and being embodied in such a manner that the upper cover is displaced by inserting an outlet pipe of a fuel nozzle into the upper entry space for releasing the upper filling opening so as to allow for the insertion of the outlet pipe through the upper filling opening and the lower sealing flap. When used for forming a protection against a filling with unsuitable fuel, the upper cover, in its closed state, is blocked by a locking element and wherein the locking element is embodied in such a manner that it is unlocked as a function of a type-specific shape of the outlet pipe of the fuel nozzle, only when the tank is filled with suitable fuel.

The invention relates to a neck end for a filler neck of a tank of amotor vehicle, in particular a neck end which can be closed without acap having an entry space, which is particularly but not necessarilydesigned as a pipe section having a funnel or pipe-like wall, whereinthe entry space can have a continuous or changing cross section of anyshape. In the following, the entry space will be identified in thisdescription as a pipe section, without this being associated with alimitation to a certain geometry.

In the pipe section, the neck end has a lower sealing flap and, abovethe lower sealing flap, a closing mechanism, which has an upper fillingopening and at least one upper cover, which at least partially coversthe upper filling opening in its closed state. The closing mechanism isthereby embodied in such a manner that the upper cover is displaced byinserting an outlet pipe of a fuel nozzle into the pipe section forreleasing the upper filling opening so as to allow for the insertion ofthe outlet pipe through the upper filling opening and the lower sealingflap. Almost throughout the world, the fuel nozzles thereby have adifferent pipe diameter for diesel fuels and gasoline.

Neck ends of this type are known from DE 203 09 799.8 U1. In this neckend, the neck is closed via two flaps, which are arranged on top of oneanother in the neck and which are held against a sealing surface by theforce of, in each case, a closing spring. The two caps are presseddownward by inserting the outlet pipe of a fuel nozzle or of a spout ofa jerry can, thus resulting in a continuous opening.

Even though these closures provide for a good seal, even without anadditional tank cap, it would still be desired if they could be furtherimproved and if they additionally had a protection against improperfueling. Particularly in the case of modern engines, it is increasinglyimportant to keep in mind safe fuel grades due to the fact that, forexample, modern injection systems of a common-rail diesel injection arelubricated via the lubricant content of the diesel fuel and can sustainheavy damages after being operated with a gasoline for only a shortoperating time.

It is thus the object of the invention to create a neck end, which canbe produced as simply as possible and which offers to minimize thedanger or an improper fueling, by using a closure, which is as safe aspossible.

According to the invention, this object is solved in that, for thepurpose of creating a protection against a filling with unsuitable fuel,the upper cover in its closed state is blocked by at least one lockingelement and in that the locking element is embodied in such a mannerthat it can be unlocked as a function of the shape of the outlet pipe ofthe fuel nozzle, only in response to a fueling with suitable fuel.

Even though the invention does not yet make every improper fuelingimpossible, the risk, however, is clearly minimized. It is commonthroughout the world that lead free gasoline is pumped by means of fuelnozzles, which have a smaller diameter of the lower end of the outletpipe than diesel fuels. This fact can thus be used according to theinvention for avoiding an unlocking of the neck end in the event thatthe incorrect fuel nozzle is used and it is as least possible to preventa fueling of a vehicle comprising a diesel engine with gasoline.

Provided that the petroleum trade is to use further fuel nozzle modelsin the future, a further increase of the error protection will obviouslybecome possible. In an ideal case, each attempt of an improper fuelingcan already be prevented if a type-specific diameter of the outlet pipeis used, which does not only contribute to the prevention of unnecessaryrepair costs, but also to the relief of impacts on the environment, inthat deficiencies must then no longer be disposed of. Car rentalcompanies can then also trust that the vehicles are no longerdeliberately or carelessly fueled with unsuitable fuel, so as to savecosts when the cars are being returned, for example, or because thedriver is not able to speak the respective language of the country andreaches for the wrong fuel nozzle out of ignorance.

When the term “cap-free” is used in the context of this application,this does obviously not refer to the fact that the filler neck does nothave an internal cap. Instead, what is meant here is that it is nolonger necessary to use a conventional tank cap in the traditionalsense, but that one could possibly be used for safety reasons. In thecontext of this application, the term “pipe section” is to describe theinflow region of the neck, which obviously does not need to have acylindrical cross section, but can have any cross section, which iseither constant or which changes across the depth of the neck.Furthermore, the range of application of the invention is not to belimited to the tank cap, even though the application will be describedbelow as the preferred use. On principle, a use is possible for allstorage tanks inside and outside of vehicle technology, in the contextof the motor vehicle in particular also in the region of the filler neckfor the engine or transmission oil.

The neck end as claimed in the invention is affected by the possibilityof locking the upper filling opening and to be able to override thislocking only if the “correct” fuel nozzle is used. This can occur inmanifold ways. One possibility is, for example, that the fuel nozzlepushes two clamping jaws, which are located opposite one another,sidewards, said clamping jaws, in turn, locking a pivot plate, whichcovers or closes the upper filling opening from below. The followingcases are possible with the fueling systems, which are presently mostfrequently used:

1. When attempting to wrongly fuel diesel fuel into a vehicle with anOtto engine, the fuel nozzle of the diesel filling pump will have alarger diameter than the “expected” fuel nozzle of the filling pump forgasoline. In this case, the fuel nozzle is too large to be inserted intothe area of operation of the filler neck; it can thus not push theclamping jaws outwards and the operator will recognize the error in thatthe upper cover cannot be opened and the fuel nozzle cannot be insertedinto the filler neck.

2. When attempting to wrongly fuel gasoline into a vehicle with a dieselengine, the fuel nozzle of the filling pump for the gasoline will have asmaller diameter than the “expected” fuel nozzle of the diesel fillingpump. The fuel nozzle is now not thick enough and will thus not be ableto simultaneously touch both clamping jaws or to even press them apart.Instead, maximally a single clamping jaw is detected so that the lockingcan then also not be disconnected herewith, even if in this case thefree end of the fuel nozzle can be inserted into the area of operation.

An advantageous embodiment of the invention provides an inclined planecomprising a laterally protruding edge as the area of the operation,wherein the outlet pipe can slide on the inclined plane. This inclinedplane represents a sliding surface for the fuel nozzle, which isinclined at an angle α relative to the longitudinal axis of the pipesection of the filler neck, which protects the upper filling openingagainst the release of the locking.

The user initially places the fuel nozzle slightly next to the actualfilling opening at the top of the sliding surface and then allows forthe outlet pipe to slide along the sliding surface. This movement canthen drive a mechanism, which causes the unlocking of the closingmechanism. This can occur, as already described above, by means ofpressing apart the clamping jaws, wherein a fuel nozzle, which is toolarge, cannot be inserted between the raised edge of the inclined planeand would thus slide on the edge, but would thus not come into contactwith the clamping jaws.

However, due to this lateral load on the outer jacket surface of theoutlet pipe, the fuel nozzle can be subjected to wear, because said fuelnozzle is typically made of aluminum and is thus only slightlywear-resistant.

Another embodiment thus presses the locking elements downward against areturn spring. This causes considerably less damage to the material andfurthermore allows for the use of springs, which are longer and betterguided. Here, a raised edge can also prevent a fuel nozzle, which is toolarge, from pressing down the locking elements, provided that thisshould be necessary. A further advantage of the raised edge lies inprotecting the locking elements against being pressed openunintentionally, for instance as a result of an accident.

When placing the outlet pipe on the inclined plane, two lockingelements, which are arranged opposite one another, are pressed down, forexample, then preferably causing a sliding of the outlet pipe on thesliding surface only at that point.

For this purpose, provision is made for a sliding element, which isdetermined by the locking and which can be unlocked by means of thedescribed mechanism. Said sliding element is mounted next to and abovethe sliding surface so as to be laterally displaceable. This slidingelement is laterally displaced after the locking elements have beendepressed by means of the outlet pipe, wherein the outlet pipe of thefuel nozzle together with the further downward movement is also furtherpushed to the side through this, until the sliding element completelyreleases the upper filling opening. Consecutively, the outlet pipe canthen be inserted into the pipe section and can depress the lower sealingflap at that location.

Further features of the neck end as claimed in the invention are highand low pressure valves. Provided that the upper cover is also embodiedso as to seal, the lower sealing flap and this upper cover can effect acorresponding pressure compensation upon the occurrence of criticalpressures, caused by heat expansion, for instance, or the removal offuel from the tank at the engine side.

A water channel, which removes water or condensate ingress, canfurthermore be arranged above the lower sealing flap, so that the wateror condensate ingress does not reach the tank during the next opening ofthe lower sealing flap.

A further aspect of the invention, which can also be applied detachedfrom the claimed cap-free filler neck, is the use of a neck end, whichcan be attached to an already known neck. According to experience, it isdifficult to carry out the basic change of the neck during a runningvehicle production for commercial-organizational reasons. If, forexample, an already constructed system is to be converted to a cap-freefueling during the production, the neck end can be attached to aninterface of the neck.

However, the driver is not to be able to remove the neck end by himself.Instead, this should be left to the expert repair shop. To prevent anunauthorized removal, the neck end can thus be provided with a retainingmeans, which can easily be attached to the filler neck, but which canonly be detached with the destruction or without destruction by using aspecial tool. Such a retaining means can be formed, for example, byspring elements, which engage in recesses according to the type of asnap ring during or after screwing the neck end onto the conventionalend piece of a filler neck and which can only be retracted by means of aspecial tool, which can be inserted, for example, between the wall ofthe filler neck and the neck end, wherein the used tool can thencontract two ends of the open snap ring and thus overrides the positivecontact.

A further feature of the invention, which can also be used independenton the concrete embodiment of the neck end as described above and asclaimed in the patent claims, can be that the neck end and the neck formtwo separate components, which can be connected with one another via aspecial connection, so that it is possible to replace the neck endwithout the filler neck itself. This has the special advantage that,after accommodating a larger amount of mechanical parts, it may bepossible that repair may be necessary more often in the region of theneck end and this can be taken care of without replacing the entireneck.

If the neck end, for example, has the above-described locking flaps,these mechanical parts could be damaged. The neck pipe itself istypically a plate or a plastic pipe. A plastic pipe, in particular, isoften also fixedly welded with a plastic tank. At any rate, thereplacement of the entire filler neck up to the tank is comparativelyextensive, because access to this region is difficult and can only bemade from the underside of the vehicle. Depending on the vehicleconstruction, the tank can also be accessible only via the interior withthe removal of further parts, so that there is a necessity to be able torepair a neck end in an easier and simpler manner than by replacing theentire filler neck.

For this purpose, the filler neck has a removable connection, similar tothe case of the neck end, which can be retrofitted, for standard bayonetor screw closures. The filler neck consists of the neck end and theactual neck pipe, which is guided to the tank and which can there beconnected with the tank so as to be removable or fixed. The connectionbetween neck end and neck pipe now occurs via a connection, which isdesigned in such a manner that it can preferably only be detached via aspecial tool. If it is not desired to exclude a possibility for misuse,the connection can also be designed so as to be capable of beingdisconnected in a simple manner.

A connection, which can be disconnected via a special tool, can beformed by resilient locking elements. These locking elements can also bedesigned here according to the type of a snap ring. The neck end canthus be slid onto the neck pipe, wherein the snap ring can be arrangedbetween the inner wall of the neck end and the outer wall of the neck.An additional seal, for instance in the shape of an O-ring, can providethe required impermeability. The ends of the snap ring can then bepressed together or apart by means of a special tool.

A further possibility lies in that the resilient elements are arrangedin the interior of the neck end and that they engage in locking recessesin the inner wall of the neck pipe through recesses in the wall of theneck end. These resilient elements can then be gripped from the insidevia the special tool and can be retracted inwards so as to be able todetach the neck end. Needless to say, all other conventional twistingmeans are also possible.

Finally, it is also possible that the neck end is initially connectedwith the neck pipe in one piece and in a fixed manner and that aremovable neck end is attached only in case repair is necessary afterremoval, for example by sawing off the defective neck end. For thispurpose, the neck pipe can already have corresponding provisions so thata replacement part can be placed according to the above-mentionedprinciples after removing the available neck end.

A further preferred embodiment of the invention has an additionalprotection against leakiness in case of an accident. This protection canalso be used independent on the specific embodiment of the neck end, asdescribed above and as claimed in the claims. Only the fact that adouble closure via an upper and a lower sealing flap is present isnecessary for this.

In case of an accident, there is always the possibility that the neckend is impinged on with an inadmissibly high shearing force, as a resultof a deforming edge or an impinging object. In this case, the shearingforce is introduced into the neck, which, without special provisions,could break at a location, which cannot be controlled. In particular dueto the fact that, on the one hand, the neck geometry is substantiallyadapted to the shape of the undercarriage and to the position of theneck end, and on the other hand, to the fuel container, a weak spot willnot occur anywhere during the course of the neck pipe, as a result of achange of the geometry, which could possibly appear as a break.

To prevent a lower breaking of the neck pipe, as this could possiblylead to a fuel escape, the neck pipe is made of a suitable material,which is break-proof on the one hand and which has a sufficientflexibility on the other hand for withstanding a certainaccident-related degree of deformation, while being free from leakage.An even better protection can be achieved in that a predeterminedbreaking point is arranged between the upper and the lower sealing flap.This predetermined breaking point causes an ultimate moment lead intothe wall of the neck end to cause the upper part of the neck end tobreak, without affecting the lower part of the neck end or even the neckpipe, which is located therebelow. In this case, the lower sealing flapis still available, which sufficiently seals the neck end so as toprevent a fuel escape even with a vehicle, which was involved in anaccident.

Preferably, provision can be made for the predetermined breaking pointby a depression, which is arranged in the wall of the neck end betweenthe upper and lower sealing flap. Said predetermined breaking point cansimply be impressed into the plastic material of the neck end or canalready be provided during production. To intensify the effect of thepredetermined breaking point, provision can be made for additionalmaterial reinforcements above and below the depression.

In the alternative, the neck end can also be embodied so as to consistof two pieces so that an upper part comprising the upper sealing flap isinserted into a lower part comprising the lower sealing flap, whereinthe connection assembly is sealed via a seal, for example an O-ring. Theupper and the lower part of the neck end then each have a pipe-shapedbasic body, being inserted into one another, by inclusion of the O-ring.

Here, the predetermined breaking point can be realized in that theconnection assembly can be severed. To prevent this from happening bymistake, the connection assembly is preferably embodied in such a mannerthat the upper and the lower part of the neck end are inseparably wedgedafter assembly of the neck end via snap-in pins, wherein the snap-inpins can break in response to an occurrence of the critical breakingforce and the upper part can be detached. In this embodiment, theoverlap region of the upper and the lower part of the neck can be keptquite small, so as to ensure a safe severing in the region of thepredetermined breaking point in response to the appearance of theshearing force.

Additional features and advantages of the invention result from thesubclaims and from the below description of a preferred exemplaryembodiment of the invention by means of the drawings.

IN THE DRAWINGS

FIG. 1 shows a side view in section onto neck end as claimed in theinvention,

FIG. 2 shows the detail “Z” from FIG. 1,

FIG. 3 shows a further embodiment of a neck end in a top view,

FIG. 4 shows a neck end comprising a predetermined breaking point in aside view in section,

FIG. 5 shows a filler neck comprising the upper part of a neck pipe anda neck end fastened thereon and

FIG. 6 shows an embodiment of the upper part of a neck end comprisinglocking pins for locking via central locking system.

FIG. 1 illustrates a side view of an exemplary embodiment as claimed inthe invention, which will be described below, without limiting theinvention or the scope of protection of the instant application to thisconcrete embodiment.

The neck end illustrated in FIG. 1 is formed by a pipe section, thecross section of which initially widens in a conical manner in thedirection of the opening. Provision is made below the widened sectionfor the lower sealing flap 2, which seals the neck. For this purpose,the sealing flap is placed against a sealing surface (not illustratedherein) via a spring. Furthermore, the neck end encompasses the high andlow pressure valves, which are reflected as detail “Z” in FIG. 2 in anenlarged illustration as well as a water discharge, which is also notillustrated here, via which the water ingress can be drained.

Initially, provision is made in the upper region for the upper fillingopening 5, through which the outlet pipe 4 of the fuel nozzle can beinserted into the neck, which then opens the lower sealing flap 2 inresponse to a further ingress. A closing mechanism 3, which prevents aninsertion of the fuel nozzle without opening said closing mechanism 3,is arranged above the upper filling opening 5.

To now minimize or, if possible, prevent improper fueling, said closingmechanism 3 is to be capable of being opened only if the “correct” fuelnozzle, that is the fuel nozzle for filling suitable fuel, is placed.

For this purpose, a ring element 14 is inserted into the upper necksection of the pipe section 1, in which, in turn, a sliding element isguided at right angles to the neck axis in a displaceable manner. Thesliding element is U-shaped, wherein it could likewise also be embodiedall around as a closed element. Substantial is here only that it has anoutlet, through which the outlet pipe 4 can be inserted.

Locking elements 7, which engage in recesses in the sliding element inthe upper region in a positive manner, are now depressed by means of theinserted outlet pipe 4. As a result of being depressed, the lockingelements 7 now disengage, the sliding element is thus released and canthen be displaced in lateral direction.

Below the sliding element, an inclined plane is embodied as a slidingsurface 10, which is incorporated into the inner jacket surface of thering element 14. Said sliding surface 10 is inclined at an angle αrelative to the neck axis of the pipe section 1 and causes a lateraldisplacement of the outlet pipe 10, which is inserted through thesliding element if it is further inserted into the pipe section 1.

As a result of the lateral displacement, the outlet pipe 4 is nowpressed against the sliding element, which, in turn, causes a lateraldisplacement of the sliding element, until the region above the upperfilling opening is completely released for the insertion of the fuelnozzle. However, this unlocking and the subsequent displacement of thesliding element is only possible, if both locking means 7, which arelocated opposite one another, are depressed by means of the lower edgeof the fuel nozzle. If the fuel nozzle is not large enough, because thediameter of the outlet pipe 10 is too small, either none or only onelocking element 7 can be depressed, which, however, does not overridethe locking.

The sliding element is embodied in such a manner that it holds thelocking elements 7 downwards after the displacement, even if the loweredge of the fuel nozzle is moved laterally towards the right and is nolonger arranged above the locking elements 7. In this stage, the leftregion of the sliding element depresses the locking elements 7.

As an alternative to the two locking elements 7, further lockingelements could certainly also be used. It is only important that theunsuitable fuel type is administered via a fuel nozzle, which cannotactuate all of the locking elements 7. The depression of the lockingelements 7 has the special advantage that a wear of the fuel nozzle islargely excluded. In particular, lateral grooves cannot be introduced.

In the illustrated preferred embodiment, the locking elements 7 are eachformed by a locking pin, which engages in a positive manner into arecess in the upper cover 6. Said locking pin can be relocated downwardthrough the free end of the outlet pipe 4 against the force of a safetyspring 9. In so doing, the locking pin “unlatches” out of the recess inthe sliding element, which is being used as the upper cover.

In terms of this protection feature, the sliding element has a blockingzone, which means nothing more than that it is arranged in closingposition with a part of its body above the upper filling opening. Saidupper filling opening is then released only by the lateral displacement.The inclined sliding surface 10 has, in particular, an inclined positionrelative to the axis of the pipe section 1 of from 20° to 80°,preferably from 35° to 55° and, as is illustrated here, more preferablyof 45°.

Preferably, as is illustrated here, the closing mechanism is protectedvia a cover cap 11, which has a long hole for inserting the outlet pipe4, wherein the width of the long hole is slightly larger than thediameter of the outlet pipe 4 and the length of the long holesubstantially corresponds to the course of displacement of the slidingelement.

Provision is made here above the upper filling opening 5 for anadditional closing cap 12, which causes an anti-theft protection and afurther seal. For this purpose, the additional closing cap 12 isflexibly arranged on the sliding element and is displaced therewith. Atthe opposite side, it engages into a locking groove 13, which fixes theadditional closing cap 12 in its closed state. After removing the fuelnozzle, a return spring resets the flap 12 so that it can again engagein the locking groove 13 when the sliding element glides back.

In addition, the locking elements can be blocked via the central lockingsystem of the motor vehicle in such a manner that an unlocking is onlypossible if the central locking system is in the opening position. Forthis purpose, an electrically driven pin can prevent a movement of thesliding element, as is already the case with the protection of knownfuel filler doors, for example.

Finally, the neck end can be designed as an independent component forconnection with a known pipe connection or it can naturally also beformed directly into the neck of a tank. If it is an independentcomponent, it can be welded with the pipe section, which is mostly madeof plastic, or it can also be connected with the neck via the standardconnection, which was used for the placement and fastening of a tank capuntil now. This has the special advantage that no change must be made tothe neck, if a vehicle is retrofitted to a cap-free fuelling.Preferably, the neck then has a removal protection, which can only bedetached by means of a tool, so that the driver himself can no longermanipulate the tank closure.

FIG. 2 reproduces the lower sealing flap 2 in an enlarged illustration.The sealing flap 2 consists of a pivot flap, which is arranged on apivot bearing 15 and which is pressed against a storage edge in the pipesection 1 of the filler neck, including a seal 16 by means of the forceof a closing spring.

In the upper part, the sealing flap 2 has a pressure region, againstwhich the lower edge of the fuel nozzle can support itself. For thepurpose of centering the fuel nozzle, provision is made in the centerregion for a ridge, which protrudes upwards. The pressure region has atleast one outlet via which pressures can enter into the interior of thesealing flap 2. The illustrated example has two outlets 17.

In the lower region, the sealing flap 2 is provided with a high pressurebypass 19 and with a low pressure bypass 18, via which low and highpressures, respectively, can be compensated. All types of pressurevalves can be used for this purpose, wherein a spring-loaded camfollower is used in the illustrated exemplary embodiment, which supportsitself with an upper rim on one side of the bottom of the sealing flapand which is guided through a passage opening in the bottom of thesealing flap with a handle body, while leaving a breathing opening,wherein a spring is clamped between the free end of the handle body andthe bottom of the sealing flap. Here, the sealing occurs via the rim,which lifts from the bottom of the sealing flap after overcoming thespring force for the actuation of the respective bypass.

FIG. 3 illustrates a further embodiment of the neck end, which, in placeof locking elements 7, which are to be pressed downward, has lockingelements 7, which are laterally displaced by the end of the outlet pipe4 of the fuel nozzle. As in the case of the illustrated exemplaryembodiment, this displacement can occur directly by means of contactwith the fuel nozzle, but it is also possible that the fuel nozzle canbe inserted into a (non-illustrated) sliding body, which must be pusheddownwards together with the end of the outlet pipe 4. This sliding bodythen has a passage opening, through which the fuel nozzle can beinserted into the neck end once the end position has been reached.

FIG. 4 illustrates a neck end as claimed in the invention comprising apredetermined breaking point 20, which, in the instant case, is formedby a depression, which is impressed into the neck wall from the outside,thus resulting here in a weakening of the material. The purpose of thispredetermined breaking point 20 is that, in the event of an inadmissibleshearing force, the upper region of the neck end can break, whilemaintaining the seal effect of the lower sealing flap 2 and the sealeffect of the filler neck thus substantially maintains, in spite of aninadmissibly high shearing force.

FIG. 5 shows the connection of a neck end comprising a pipe connection23 of a tank neck system, which is embodied in two pieces, wherein theneck end, however, can only be detached from the pipe connection 23 withthe destruction of the connection element or by means of a special tool.

For the connection with the pipe connection 23, the neck end is pushedonto the pipe connection, wherein resilient holding elements 22 engageinto recesses of the pipe connection 23 in such a manner that adetaching is only possible with the destruction of the resilient holdingedges 24 or by inserting the tool. For the positive connection with theends, the engaged resilient holding elements 22 engage around holdingedges 24 of the pipe connection 23, so that the neck end is held tight.A seal (which is not illustrated here) seals the connection.

FIG. 6 illustrates a further embodiment of the filler neck as claimed inthe invention, where provision is made for a locking pin 21, which canbe actuated via the switching elements of a central locking system ofthe motor vehicle. This bolt-shaped locking pin 21 incorporates the neckend into the central locking system of the motor vehicle, in that itpushes against the upper cover 6, when in its closed state, so that saidupper cover 6 cannot be displaced. As a result, the additional closingcap 12, which forms the upper sealing flap in the illustrated exemplaryembodiment, cannot be disengaged from the locking groove 13, the uppersealing flap in the form of the closing cap 12 thus remaining closed,provided that the locking pin 21 remains depressed. Said locking pin 21is retracted only in response to an opening of the central lockingsystem, so that the fueling system is released by means of the centrallocking system.

The locking pin 21 also permits further additional functions. In theevent of a running engine, for example, the vehicle electronics canautomatically place the locking pin against the upper cover 6, so that afueling of the vehicle is only possible if the engine is turned off. Thefueling of a vehicle while an external heater, in particular anauxiliary heating system, is turned on is also prevented via the samefunction. This increases the protection against careless disregard ofregulations by the driver.

Furthermore, the function of the locking pin 21 can also be coupled tocrash sensors or other elements of the control of the driving dynamicsso that the neck end is once again closed in time prior to the vehiclebeing involved in an accident so that the inherently impossible casethat the upper cover 6 is pushed away by a foreign object or by adeforming chassis edge can additionally be prevented.

It goes without saying that the locking pin 21 can also be arranged atany other position of the cap. It is even possible that the locking pinis embodied in a disk-shaped manner and that it can be moved in lateraldirection in front of the pipe opening as an additional sealing flap.

The locking of a pivot flap, which is typically provided in a vehiclefor covering the tank neck can now become dispensable by means of thelocking pin 21. On the one hand, this enables again the previouslyconducted design of the chassis comprising a visible neck end, where,for example the upper cover can be made of stainless steel for creatingan interesting optical effect and furthermore saves the displacement ofthe locking pin 21 against an area of sheet metal of the chassis, whichis located relatively far outside, which could possibly be damagedthrough this, if perhaps the pivot flap is not completely closed and thelocking pin 21 is not displaced into the provided opening, but insteadpushes against the edge of said opening.

In connection with the predetermined breaking point 20, provision canalso be made for the locking pin 21 in the region of the lower sealingflap 2, either as a single locking pin 21 or as an additional lockingpin 21. This would have the advantage that the locking will not beoverridden by breaking off the upper neck end. This could not beoverridden again by breaking off the locked part, particularly if alocking is to take place automatically in connection with the crashsensor system.

It is necessary for the central locking system function of the neck endthat provision is made for a locking pin 21 that fixes one of thepivotable sealing flaps regarding to their pivoting movement, or thatblocks the movability of the one longitudinally movable functionalregion of the neck end was blocked, provided that the accessibility intothe interior of the pipe connection 23 is provided by the longitudinalmovability.

The provision of the predetermined breaking point 20 as well as thecomplex central locking system and the embodiment of the filler neck asa two-piece component comprising an upper neck end and lower pipe neck,which is connected therewith only with the destruction of the connectionis presently considered to be an independent invention complex, which isnot required to be in connection with the special embodiment of the neckend in the region of the upper and the lower seal. It is thus reservedto direct independent claims to these three complexes.

LIST OF REFERENCE NUMERALS

-   1 pipe section-   2 lower sealing flap-   3 closing mechanism-   4 outlet pipe-   5 upper filling opening-   6 upper cover-   7 locking element-   8 closing spring-   9 safety spring-   10 sliding surface-   11 cover cap-   12 additional closing flap-   13 locking groove-   14 holding ring-   15 pivot bearing of the sealing flap-   16 seal of the sealing flap-   17 outlet in the pressure region of the sealing flap-   18 low pressure bypass-   19 high pressure bypass-   20 predetermined breaking point-   21 locking pin-   22 resilient holding elements-   23 pipe connection-   24 holding edge-   α angle of inclination of the sliding surface relative to the    longitudinal axis of the pipe sec

1-36. (canceled)
 37. A cap-free closeable neck end for a filler neck ofa tank of a motor vehicle, comprising: an upper entry space forming aninsertion region for a fuel nozzle and being surrounded by a side wall;a lower sealing flap arranged in the upper entry space; a closingmechanism arranged above the lower sealing flap, wherein the closingmechanism comprises: an upper filling opening; and an upper cover, whichin a closed state at least partially covers the upper filling openingand being embodied in such a manner that the upper cover is displaced byinserting an outlet pipe of a fuel nozzle into the upper entry space forreleasing the upper filling opening so as to allow for the insertion ofthe outlet pipe through the upper filling opening and the lower sealingflap and wherein for forming a protection against a filling withunsuitable fuel, the upper cover, in its closed state, is blocked by alocking element and wherein the locking element is embodied in such amanner that it is unlocked as a function of a type-specific shape of theoutlet pipe of the fuel nozzle, only when the tank is filled withsuitable fuel.
 38. The cap-free closeable neck end for a filler neck ofa tank of a motor vehicle according to claim 37, wherein the entry spaceis embodied as a pipe section comprising a constant or changeable crosssection and in that the locking element is formed by a blocking device,which is mounted in such a manner that the blocking device is displacedby the outlet pipe for unlocking the upper cover out of a blockingposition.
 39. The cap-free closeable neck end for a filler neck of atank of a motor vehicle according to claim 38, further comprising asliding surface above the upper filling opening arranged at an angle (α)to a longitudinal axis of the pipe section, along which the outlet pipe,upon being inserted into the pipe section, is guided so as to slide froma starting position, which is laterally offset to the upper fillingopening, up to an insertion position, which is congruent with the upperfilling opening.
 40. The cap-free closeable neck end for a filler neckof a tank of a motor vehicle according to claim 37, further comprising asecond locking element, wherein the locking element and the secondlocking element are arranged at a distance (a) to one another, whereinthe distance (a) is so large that the locking element and the secondlocking element are unlocked by the outlet pipe of the fuel nozzlecomprising a first diameter, in particular a fuel nozzle for dieselfuel, while at most the locking element is unlocked by a second fuelnozzle comprising a second diameter, which is smaller relative to thefirst diameter.
 41. The cap-free closeable neck end for a filler neck ofa tank of a motor vehicle according to claim 40, wherein the lockingelement and the second locking element are located opposite one anotherand are displaced for unlocking the upper cover from a free end of theoutlet pipe with a suitable diameter.
 42. The cap-free closeable neckend for a filler neck of a tank of a motor vehicle according claim 37,wherein the locking element comprises a locking pin that engages with arecess in the upper cover in a positive manner and which is displacedlaterally or downward against a force of a safety spring through a freeend of the outlet pipe, wherein, upon completion of displacement of thelocking pin, engagement of the locking pin with the recess of the uppercover is overridden.
 43. The cap-free closeable neck end for a fillerneck of a tank of a motor vehicle according to claim 39, wherein theupper cover is formed by a pivot flap, which is pivoted against a forceof a closing spring from a closed state into an open state and in thatthe locking element comprises: an upper region, which can be displacedby the outlet pipe with a suitable diameter when a free end of theoutlet pipe is placed on or slides on the sliding surface for unlockingthe outlet pipe with a suitable diameter; and a lower region, whichengages around the pivot flap, which is pivotable inwardly in adirection of the tank in a bolt-like manner, when in closed state,wherein for unlocking engagement is overridden by displacement of thelocking element.
 44. The cap-free closeable neck end for a filler neckof a tank of a motor vehicle according to claim 38, wherein the uppercover comprises a laterally slidable sliding element, which is displacedfrom an end of the outlet pipe at least in a lateral direction.
 45. Thecap-free closeable neck end for a filler neck of a tank of a motorvehicle according to claim 44, wherein the sliding element at leastpartially covers the upper filling opening comprising a locking regionand in that the end of the outlet pipe is placed laterally next to thelocking region, wherein, when the outlet pipe slides on the slidingsurface along a sliding direction the outlet pipe is pushed against thelocking region in the sliding direction and displacement of the slidingelement is thus effected.
 46. The cap-free closeable neck end for afiller neck of a tank of a motor vehicle according to claim 45, whereinthe sliding element has a U-shaped inner region comprising twosubstantially straight legs and a curved center region, wherein thelocking region is formed by a part of the center region and wherein thesliding surface is arranged next to the center region and is at leastpartially covered by the straight legs.
 47. The cap-free closeable neckend for a filler neck of a tank of a motor vehicle according to claim46, wherein the sliding surface is an inclined plane that is inclined atan angle (α) relative to an axis of the pipe section that has a valuethat is between 20° and 80°, preferably between 35° and 55° and, morepreferably, 45°.
 48. The cap-free closeable neck end for a filler neckof a tank of a motor vehicle according to claim 46, wherein the recessfor engaging the locking element is arranged in the straight legs of thesliding element, wherein the locking element protrude inwardly from therecess to such an extent that the locking element is pressed down onlyby the outlet pipe having a sufficiently large diameter and that asecond outlet pipe comprising a diameter, which is too small, cannotpress down the locking element.
 49. The cap-free closeable neck end fora filler neck of a tank of a motor vehicle according to claim 46,wherein a part of the straight legs, which faces away from a centerregion of the sliding element, is designed in such a manner that, aftersuch a sliding of the outlet pipe in a direction of the upper fillingopening, the outlet pipe no longer covers the locking element, thelocking element being held down by the straight legs on a furtherdisplacement path, until the outlet pipe is inserted into the upperfilling opening.
 50. The cap-free closeable neck end for a filler neckof a tank of a motor vehicle according to one of claim 49, wherein aninner curvature of the center region of the sliding elementsubstantially corresponds to an outer curvature of the outlet pipe. 51.The cap-free closeable neck end for a filler neck of a tank of a motorvehicle according to claim 44, wherein within the pipe section, abovethe upper filling opening, a holding ring is inserted, in which thesliding element is guided so as to be slidable.
 52. The cap-freecloseable neck end for a filler neck of a tank of a motor vehicleaccording to claim 44, further comprising a cover cap having a long holefor inserting the outlet pipe, wherein a width of the long hole isslightly greater than the diameter of the outlet pipe and a length ofthe long hole substantially corresponds to a displacement path of thesliding element.
 53. The cap-free closeable neck end for a filler neckof a tank of a motor vehicle according to claim 37, further comprising asecond sealing flap, wherein the second sealing flap is positioned abovethe upper filling opening and is pushed open by the outlet pipe againsta spring force.
 54. The cap-free closeable neck end for a filler neck ofa tank of a motor vehicle according to claim 53, wherein the secondsealing flap is mounted on a sliding element in a flexible manner andengages with a partial region opposite of a joint into a locking groovein a pipe section or with a component, which is stationary relative tothe pipe section, when the closing mechanism is in a closed position.55. The cap-free closeable neck end for a filler neck of a tank of amotor vehicle according to claim 37, wherein the motor vehicle comprisesa central locking system, and wherein the locking element isadditionally blocked via the central locking system of the motor vehiclein such a manner that an unlocking is only possible if the centrallocking system is in an opening position.
 56. The cap-free closeableneck end for a filler neck of a tank of a motor vehicle according toclaim 38, wherein the pipe section comprises high and/or low pressurevalves, via which a high pressure or low pressure in the tank can beequalized by bridging a sealing function of the upper filling openingand/or of the lower sealing flap.
 57. The cap-free closeable neck endfor a filler neck of a tank of a motor vehicle according to claim 56,wherein the lower sealing flap is mounted so as to be displaceableagainst a force of a respective valve spring in both directions of anaxis of the pipe section, wherein a displacement of the lower sealingflap causes a respective valve function of the high or low pressurevalve.
 58. The cap-free closeable neck end for a filler neck of a tankof a motor vehicle according to claim 55, further comprising: a firstbypass that opens in a first direction in response to a firstdisplacement of a valve body as a result of a high pressure; and asecond bypass that opens in a second direction in response to a seconddisplacement of a valve body as a result of a low pressure.
 59. Thecap-free closeable neck end for a filler neck of a tank of a motorvehicle according to claim 37, wherein the cap-free closeable neck isconnected in one piece with a pipe connection of a fuel supply system ofthe motor vehicle.
 60. The cap-free closeable neck end for a filler neckof a tank of a motor vehicle according to one of claim 37, wherein thecap-free closeable neck is screwed onto a common fastening for a tankcap on a tank neck.
 61. The cap-free closeable neck end for a fillerneck of a tank of a motor vehicle according to claim 60, wherein thecap-free closeable neck a removal protection, which can only be removedby a tool.
 62. The cap-free closeable neck end for a filler neck of atank of a motor vehicle according to claim 61, wherein the removalprotection is formed by spring elements, which, engaging around asurface in a resilient manner in response to a placement of the neck endon a tank neck, block the removal, wherein the spring elements aregripped via a gripper and are retracted for deactivating the removalprotection.
 63. The cap-free closeable neck end for a filler neck of atank of a motor vehicle according to claim 37, wherein provision is madeabove the lower sealing flap for a water removal for water or condensateingress.
 64. The cap-free closeable neck end for a filler neck of a tankof a motor vehicle according to claim 55, further comprising an upperlocking element that is controlled via the central locking system, inparticular in the form of a locking pin, which, in a locked state, locksthe upper closing element and is switched into an open state via thecentral locking system, in which the upper locking element is opened byinserting the outlet pipe.
 65. The cap-free closeable neck end for afiller neck of a tank of a motor vehicle according to claim 55, furthercomprising a lower locking element controlled via the central lockingsystem, in particular in the form of a locking pin, which, in a lockedstate, blocks the lower sealing flap and which is switched into an openstate via the central locking system, in that the lower sealing flap ispivotable by the penetrating outlet pipe.
 66. The cap-free closeableneck end for a filler neck of a tank of a motor vehicle according toclaim 64, wherein the upper locking element together with the centrallocking system switches into the open state and the locked state. 67.The cap-free closeable neck end for a filler neck of a tank of a motorvehicle according to claim 65, wherein the lower locking elementtogether with the central locking system switches into the open stateand the locked state.
 68. The cap-free closeable neck end for a fillerneck of a tank of a motor vehicle according to claim 64, wherein thecentral locking system switches the upper locking element into a lockedstate in response to a running engine or another device, which is notpermitted during fueling, and the release of the filler neck only occursafter the engine or the another device has been turned off.
 69. Thecap-free closeable neck end for a filler neck of a tank of a motorvehicle according to claim 65, wherein the central locking systemswitches the lower locking element into a locked state in response to arunning engine or another device, which is not permitted during fueling,and the release of the filler neck only occurs after the engine or theanother device has been turned off.
 70. The cap-free closeable neck endfor a filler neck of a tank of a motor vehicle of claim 55, furthercomprising a sensor in the form of a crash detector or a drivingdynamics and rollover sensor, respectively, wherein, upon identificationof a critical situation, the sensor transmits an alarm signal toon-board electronics, which control the central locking system whereinthe locking element is closed in response to the occurrence of the alarmsignal.
 71. The cap-free closeable neck end for a filler neck of a tankof a motor vehicle, comprising: a wall for enclosing an inflow region; alower sealing flap; an upper cap-free closing mechanism; and a lowersealing flap, wherein the wall includes a region with a predeterminedbreaking point located between the upper cap-free closing mechanism andthe lower sealing flap.
 72. The cap-free closeable neck end for a fillerneck of a tank of a motor vehicle according to claim 71, wherein theregion comprises a wall thickness that is thinner than other portions ofthe wall.
 73. The cap-free closeable neck end for a filler neck of atank of a motor vehicle according to claim 72, wherein the regioncomprises a revolving groove, which is impressed into the wall.
 74. Afiller neck of a tank of a motor vehicle, comprising: a pipe connection,which is connected with the tank; and a neck end connected with the pipeconnection via a connection, which cannot be detached without beingdestroyed or without a tool.
 75. The cap-free closeable neck end for afiller neck of a tank of a motor vehicle according to claim 74, whereinthe connection is formed by resilient holding elements that are arrangedbetween the neck end and the pipe connection, and wherein the resilientholding elements are displaced when the neck end is slid onto the pipeconnection and holding edges resiliently engage with accommodations forforming a positive connection in a position of use and being designed insuch a manner that the holding edges wedge automatically in response toa stress in the opposite direction.